Adapter assembly for interconnecting electromechanical surgical devices and surgical loading units, and surgical systems thereof

ABSTRACT

The present disclosure relates to an adapter assembly for electrically and mechanically interconnecting electromechanical surgical devices and surgical loading units. The adapter assembly includes an articulation assembly having a rotatable drive shaft having a proximal end rotatable by a surgical device and a distal end having a gear with external teeth, a gear nut including external gear teeth meshingly engaged with the external teeth of the gear, a screw disposed within the gear nut and including external threads engaged with internal threads of the gear nut such that the screw is axially moveable relative to the gear nut, and an articulation bar operably coupled to the screw such that axial movement of the screw results in corresponding axial movement of the articulation bar.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application Ser. No. 62/259,351 filed Nov. 24, 2015, the entiredisclosure of which is incorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to adapter assemblies for use in surgicalsystems. More specifically, the present disclosure relates to adapterassemblies for use with, and to electrically and mechanicallyinterconnect, electromechanical surgical devices and surgical loadingunits.

BACKGROUND

A number of surgical device manufacturers have developed product lineswith proprietary powered drive systems for operating and/or manipulatinga surgical device. In many instances the surgical devices include apowered handle assembly, which is reusable, and a disposable endeffector or the like that is selectively connected to the powered handleassembly prior to use and then disconnected from the end effectorfollowing use in order to be disposed of or in some instances,sterilized for re-use.

Many of the existing end effectors for use with many of the existingpowered surgical devices and/or handle assemblies are driven by a linearforce. For examples, end effectors for performing endo-gastrointestinalanastomosis procedures, end-to-end anastomosis procedures and transverseanastomosis procedures, each typically require a linear driving force inorder to be operated. As such, these end effectors are not compatiblewith surgical devices and/or handle assemblies that use a rotary motionto deliver power or the like.

In order to make the linear driven end effectors compatible with poweredsurgical devices and/or handle assemblies that use a rotary motion todeliver power, adapters and/or adapter assemblies are used to interfacebetween and interconnect the linear driven end effectors with thepowered rotary driven surgical devices and/or handle assemblies. Forexample, a plurality of rotary motion to linear motion convertingassemblies may extend through an adapter to effect different functionsof an end effector. Components of these assemblies, however, may requiremore input torque to generate a linear force if, for example, theassemblies include a gear assembly having a low gear ratio and/or theoutput force is not axial to the load.

Accordingly, a need exists for an adapter for a powered rotary drivensurgical device that requires less rotary motor torque to generate alinear force.

SUMMARY

According to one embodiment of the present disclosure, an adapterassembly for selectively interconnecting a surgical loading unit and asurgical device is provided. The adapter assembly includes: an adapterhousing configured to connect to a surgical device; an outer tube havinga proximal end supported by the adapter housing and a distal endconfigured to connect to a surgical loading unit; and a transmissionassembly at least partially disposed within the adapter housing. Thetransmission assembly includes: a proximal rotation receiving memberconnectable to a drive shaft of a surgical device; a distal forcetransmitting member connectable to an axially translatable drive memberof a surgical loading unit; at least one pin securely disposed withinthe adapter housing; and a bearing assembly coupled to the proximalrotation receiving member and the distal force transmitting member. Thebearing assembly is axially movable along the at least one pin inresponse to rotational motion of the proximal rotation receiving memberthereby axially moving the distal force transmitting member.

According to a further embodiment of the present disclosure, anelectromechanical surgical system is provided. The electromechanicalsurgical system includes a surgical loading unit including a proximalbody portion and a tool portion, and an axially translatable drivemember; a surgical device including a device housing and at least onerotatable drive shaft supported in the device housing; and an adapterassembly configured to selectively interconnect the surgical loading andthe surgical device. The adapter assembly includes an adapter housingconfigured to connect to the surgical device; an outer tube having aproximal end supported by the adapter housing and a distal endconfigured to connect to the surgical loading unit; and a transmissionassembly at least partially disposed within the adapter housing. Thetransmission assembly includes: a proximal rotation receiving memberconnectable to the rotatable drive shaft of the surgical device; adistal force transmitting member connectable to the axially translatabledrive member of the loading unit; at least one pin securely disposedwithin the adapter housing; and a bearing assembly coupled to theproximal rotation receiving member and the distal force transmittingmember. The bearing assembly is axially movable along the at least onepin in response to rotational motion of the proximal rotation receivingmember thereby axially moving the distal force transmitting member.

According to an aspect of any of the above embodiments, the bearingassembly is non-rotatably disposed within the adapter housing. Thebearing assembly also includes a bearing housing and a bearing rotatablydisposed within the bearing housing.

According to another aspect of any of the above embodiments, the distalforce transmitting member is coupled to an inner race of the bearing.

According to a further aspect of any of the above embodiments, thebearing housing further includes a threaded bore threadably coupled to athreaded distal end of the proximal rotation receiving member. Thethreaded bore includes an insert molded threaded member, which is formedfrom a polymer selected from the group consisting of fluoropolymers,polystyrenes, and polyaryletherketones.

According to yet another aspect of any of the above embodiments, the atleast one pin is coupled to a support ring member disposed within theadapter housing.

According to yet further aspect of any of the above embodiments, theaxially translatable drive member is configured to articulate the toolportion of the surgical loading unit.

Further details and aspects of exemplary embodiments of the presentdisclosure are described in more detail below with reference to theappended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosureand, together with a general description of the disclosure given above,and the detailed description of the embodiment(s) given below, serve toexplain the principles of the disclosure, wherein:

FIG. 1 is a perspective view of an electromechanical surgical systemincluding a handheld surgical device, an adapter assembly, and asurgical loading unit in accordance with the principles of the presentdisclosure;

FIG. 2 is a perspective view illustrating a connection of the adapterassembly and the handheld surgical device of the electromechanicalsurgical system of FIG. 1;

FIG. 3 is a perspective view of the adapter assembly of FIGS. 1 and 2,with most parts separated;

FIG. 4 is a cross-sectional view of the adapter assembly of FIGS. 1-3,taken along section line “4-4” of FIG. 1;

FIG. 5 is a cross-sectional view of the adapter assembly of FIGS. 1-4,taken along section line “5-5” of FIG. 1;

FIG. 6 is a perspective view, with parts removed, of an outer housing ofthe adapter assembly of FIGS. 1-5; and

FIG. 7 is a perspective view, with parts separated, of the surgicalloading unit of FIG. 1.

DETAILED DESCRIPTION

Electromechanical surgical systems of the present disclosure includesurgical devices in the form of powered handheld electromechanicalinstruments configured for selective attachment to a plurality ofdifferent end effectors that are each configured for actuation andmanipulation by the powered handheld electromechanical surgicalinstrument. In particular, the presently described electromechanicalsurgical systems include adapter assemblies that interconnect thepowered handheld electromechanical surgical instruments to the pluralityof different end effectors. Each adapter assembly includes a firingassembly, an articulation assembly, and a rotation assembly that isoperatively coupled to a powered handheld electromechanical surgicalinstrument for effectuating actuation and/or manipulation of theplurality of different end effectors.

Embodiments of the presently disclosed electromechanical surgicalsystems, surgical devices/handle assemblies, adapter assemblies, and/orloading units are described in detail with reference to the drawings, inwhich like reference numerals designate identical or correspondingelements in each of the several views. As used herein the term “distal”refers to that portion of the system, assembly, device, and/or componentthereof, farther from the user, while the term “proximal” refers to thatportion of the system, assembly, device, and/or component thereof,closer to the user.

Turning now to FIG. 1, an electromechanical surgical system, inaccordance with the present disclosure, generally referred to as 10,includes a surgical device 100 in the form of a powered handheldelectromechanical instrument, an adapter assembly 200, and a surgicalloading unit 300 (e.g., an end effector, multiple- or single-use loadingunit). Surgical device 100 is configured for selective connection withadapter assembly 200, and, in turn, adapter assembly 200 is configuredfor selective connection with surgical loading unit 300. Together,surgical device 100 and adapter assembly 200 may cooperate to actuatesurgical loading unit 300.

Surgical device 100 includes a handle housing 102 including a circuitboard (not shown) and a drive mechanism (not shown) situated therein.The circuit board is configured to control the various operations ofsurgical device 100. Handle housing 102 defines a cavity therein (notshown) for selective removable receipt of a rechargeable battery (notshown) therein. The battery is configured to supply power to any of theelectrical components of surgical device 100. Handle housing 102supports a plurality of motors (not shown), each in electricalcommunication with the circuit board and each including a rotatabledrive shaft extending therefrom.

Handle housing 102 includes an upper housing portion 102 a which housesvarious components of surgical device 100, and a lower hand grip portion102 b extending from upper housing portion 102 a. Lower hand gripportion 102 b may be disposed distally of a proximal-most end of upperhousing portion 102 a. The location of lower housing portion 102 brelative to upper housing portion 102 a is selected to balance a weightof a surgical device 100 that is connected to or supporting adapterassembly 200 and/or surgical loading unit 300.

Handle housing 102 provides a housing in which the drive mechanism (notshown) is situated. The drive mechanism is configured to drive shaftsand/or gear components in order to perform the various operations ofsurgical device 100. In particular, the drive mechanism is configured todrive shafts and/or gear components in order to selectively articulatesurgical loading unit 300 about a central longitudinal axis “X” andrelative to a distal end of adapter assembly 200, to selectively rotatesurgical loading unit 300 about longitudinal axis “X” and relative tohandle housing 102, to selectively move/approximate/separate an anvilassembly 306 and a cartridge assembly 308 of surgical loading unit 300relative to one another, and/or to fire a stapling and cutting cartridgewithin cartridge assembly 308 of surgical loading unit 300.

As shown in FIG. 2, in conjunction with FIG. 1, handle housing 102 ofsurgical device 100 defines a connection portion 104 configured toaccept a proximal end of adapter assembly 200. Connection portion 104houses an electrical pass-through connector 105 in electricalcommunication with the circuit board (not shown) and a plurality ofrotatable drive shafts or connectors 106. Each rotatable drive connectorof the plurality of rotatable drive connectors 106 can be independently,and/or dependently, actuatable and rotatable by the drive mechanism ormotors (not shown) housed within housing handle 102. In embodiments, theplurality of rotatable drive connectors 106 includes first, second, andthird rotatable drive connectors, 106 a, 106 b, and 106 c arranged in acommon plane or line with one another. As can be appreciated, theplurality of rotatable drive connectors 106 can be arranged in anysuitable configuration. The drive mechanism (not shown) may beconfigured to selectively drive one of the rotatable drive connectors106 of surgical instrument 100, at a given time.

Handle housing 102 supports a plurality of finger-actuated controlbuttons, rocker devices, and the like for activating various functionsof surgical device 100. For example, handle housing 102 supports aplurality of actuators including, for example, an actuation pad 108 toeffectuate, for example, opening, closing, and/or firing of surgicalloading unit 300. Handle housing 102 can support actuators 109 a, 109 bwhich can be disposed in electrical communication with the motors ofhandle housing 102 to effectuate, for example, rotation of first,second, and/or third rotatable drive connectors 106 a, 106 b, and/or 106c for actuation thereof to enable adjustment of one or more of thecomponents of adapter assembly 200. Any of the presently describedactuators can have any suitable configuration (e.g., button, knob,toggle, slide, etc.).

Reference may be made to International Application No.PCT/US2008/077249, filed Sep. 22, 2008 (Inter. Pub. No. WO 2009/039506),and U.S. Patent Application Publication No. 2011/0121049, filed on Nov.20, 2009, the entire contents of each of which being incorporated hereinby reference, for a detailed description of various internal componentsof and operation of exemplary electromechanical surgical systems, thecomponents of which are combinable and/or interchangeable with one ormore components of electromechanical surgical systems 10 describedherein.

With reference to FIGS. 1-3, adapter assembly 200 includes an outerhousing 202 and an outer tube 204 that extends distally from outerhousing 202 to a distal cap 206 thereof along central longitudinal axis“X.” Outer housing 202 and outer tube 204 are configured and dimensionedto house the components of adapter assembly 200. Outer housing 202 ofadapter assembly 200 includes a proximal housing 202 a and a distalhousing 202 b. Proximal housing 202 a defines a cavity 203 a therein andhas a distal lip 203 b extending radially outwardly therefrom. Distalhousing 202 b includes a first half-section 208 a and a secondhalf-section 208 b that are configured and adapted to mate together.Each of first and second half-sections 208 a and 208 b defines aninternal lip receiving annular recess 209 a adapted to receive a portionof distal lip 203 b of proximal housing 202 a to facilitate securementof proximal and distal housings 202 a and 202 b. Each of first andsecond half-sections 208 a and 208 b defines anarticulation-assembly-receiving recess 209 b that is in communicationwith an outer-tube-receiving channel 209 c. Each outer-tube-receivingchannel 209 c is defined through a distal end of one of first and secondhalf-sections 208 a and 208 b.

A mounting assembly 210 is supported on proximal housing 202 a of outerhousing 202 for attachment/detachment of the adapter assembly 200 tosurgical device 100. Mounting assembly 210 includes a shaft 212 thatextends outwardly from proximal housing 202 a, a spring 214 that issupported about an outer surface of shaft 212, and a mounting button 216that engages spring 214 and shaft 212. Spring 214 contacts a bottomsurface of mounting button 216 to bias mounting button 216 upwardly toan extended position spaced from proximal housing 202 a. Spring 214 issufficiently compressible to enable mounting button 216 to be depresseddownwardly from the extended position to a compressed position. In thecompressed position, mounting button 216 is disposed in closeapproximation with proximal housing 202 a and offset from the extendedposition. Mounting button 216 includes sloped engagement features 216 athat are configured to contact connection portion 104 (FIG. 1) of handlehousing 102 while mounting button 216 is in the extended position tofacilitate securement of proximal housing 202 a to connection portion104 of handle housing 102.

Proximal housing 202 a of outer housing 202 rotatably supports first,second and third connector sleeves 220, 222, and 224, respectively,arranged in a common plane or line with one another. Each of the first,second, and third connector sleeves 220, 222, and 224 is configured tomate with respective first, second and third rotatable drive connectors106 a, 106 b, and 106 c of surgical device 100.

Adapter assembly 200 also includes a first, a second, and a thirdbiasing member 226, 228, and 230 disposed distally of respective first,second and third connector sleeves 220, 222, and 224. First, second, andthird biasing members 226, 228, and 230 act on respective first, second,and third connector sleeves 220, 222, and 224 to help maintainengagement of first, second, and third connector sleeves 220, 222, and224 with the distal end of respective first, second, and third rotatabledrive connectors 106 a, 106 b, and 106 c of surgical device 100 whenadapter assembly 200 is connected to surgical device 100. First, second,and third biasing members 226, 228, and 230 contact or rest against aplate bushing 232 disposed within proximal housing 202 a, and functionto bias respective first, second, and third connector sleeves 220, 222,and 224 in a proximal direction.

Plate bushing 232 is secured to an inner housing 234 of adapter assembly200. The plate bushing 232 and inner housing 234 each define a pluralityof apertures (not explicitly shown) that are arranged in the commonplane or line of first, second, and third connector sleeves 220, 222,and 224 for rotatably supporting a first rotatable drive shaft 242, asecond rotatable drive shaft 252, and a third rotatable drive shaft 272,respectively, of first, second, and third force/rotationtransmitting/converting assemblies 240, 250, and 270 (FIG. 4) disposedwithin outer housing 202 and outer tube 204 of adapter assembly 200.Each of the first, second, and third connector sleeves 220, 222, and 224is configured to mate with a proximal end of respective first, second,and third rotatable drive shafts 242, 252, and 272, and each of thefirst, second, and third rotatable drive shafts 242, 252, and 272functions as a rotation receiving member to receive rotational forcesfrom respective first, second, and third rotatable drive connectors 106a, 106 b, and 106 c of surgical device 100.

Each of the force/rotation transmitting/converting assemblies 240, 250,and 270 is configured and adapted to transmit/convert a speed/force ofrotation (e.g., increase or decrease) of first, second and thirdrotatable drive connectors 106 a, 106 b, and 106 c of surgical device100 into axial translation and/or rotation of components offorce/rotation transmitting/converting assemblies 240, 250, and 270 toeffectuate a function of surgical loading unit 300, as described ingreater detail below.

As shown in FIGS. 3-5, first force/rotation transmitting/convertingassembly or drive assembly 240 of adapter assembly 200 includes firstrotatable drive shaft 242 which, as described above, is rotatablysupported within outer housing 202. First rotatable drive shaft 242includes a proximal portion 242 a having a non-circular or shapedproximal end 242 b configured for connection with first connector sleeve220 which is connected to respective first rotatable drive connector 106a of surgical device 100 (FIG. 2), and a distal portion 242 c having athreaded outer profile or surface. A housing bearing member 218, such asa thrust bearing, receives and supports proximal portion 242 a of firstrotatable drive shaft 242 to enable first rotatable drive shaft 242 torotate.

First force/rotation transmitting/converting assembly 240 furtherincludes a drive coupling nut 244 rotatably coupled to threaded distalportion 242 c of first rotatable drive shaft 242, and which is slidablydisposed within a center tube 205 that is at least partially disposedwithin both outer housing 202 and outer tube 204, and concentric withcentral longitudinal axis “X.” Drive coupling nut 244 is slidably keyedwith center tube 205 so as to be prevented from rotating as firstrotatable drive shaft 242 is rotated. In this manner, as first rotatabledrive shaft 242 is rotated, drive coupling nut 244 is translated alongthreaded distal end portion 242 c of first rotatable proximal driveshaft 242 and, in turn, through/along outer tube 204.

First force/rotation transmitting/converting assembly 240 furtherincludes a distal drive member 246 that is mechanically engaged withdrive coupling nut 244, such that axial movement of drive coupling nut244 results in a corresponding amount of axial movement of distal drivemember 246. Distal end portion 246 a of distal drive member 246 supportsa connection member 248 configured and dimensioned for selectiveengagement with a drive member 324 of drive assembly 320 of surgicalloading unit 300 (FIG. 7). Drive coupling nut 244 and/or distal drivemember 246 function as a force transmitting member to components ofsurgical loading unit 300.

In operation, as first rotatable drive shaft 242 is rotated, due to arotation of first connector sleeve 220, as a result of the rotation offirst rotatable drive connector 106 a of surgical device 100, drivecoupling nut 244 is caused to translate axially along threaded distalend portion 242 c of first rotatable drive shaft 242, which in turn,causes distal drive member 246 to translate axially relative to outertube 204. As distal drive member 246 is translated axially, withconnection member 248 connected thereto and engaged with drive member324 of drive assembly 320 of surgical loading unit 300, distal drivemember 246 causes concomitant axial translation of drive member 324 ofsurgical loading unit 300 to effectuate opening or closing of a toolassembly 304 and/or a firing of tool assembly 304 of surgical loadingunit 300 (FIG. 7).

A lock mechanism 236 is supported on the distal housing 202 b for fixingthe axial position and radial orientation of distal drive member 246.Lock mechanism 236 includes a button 236 a slidably supported on distalhousing 202 b of outer housing 202 of adapter assembly 200. Button 236 ais connected to an actuation bar 236 b that extends longitudinallythrough outer tube 204. Actuation bar 236 b moves upon movement ofbutton 236 a. Button 236 a is configured to be moved from a distalposition to a proximal position to lock or prevent distal drive member246 from distal and/or proximal movement, and from a proximal positionto a distal position to allow unimpeded axial translation and radialmovement of distal drive member 246.

In operation, in order to lock the position and/or orientation of distaldrive member 246, a user moves button 236 a of lock mechanism 236 from adistal position to a proximal position, thereby causing a lock out (notshown) to move proximally such that a distal face of the lock out movesout of contact with a camming member 238, which causes camming member238 to cam into recess 246 b of distal drive member 246. In this manner,distal drive member 246 is prevented from distal and/or proximalmovement. When button 2364 a of lock mechanism 236 is moved from theproximal position to the distal position, actuation bar 236 b movesdistally into the lock out (not shown), against the bias of a biasingmember (not shown), to force the camming member 238 out of recess 246 bof distal drive member 246, thereby allowing unimpeded axial translationand radial movement of distal drive member 246.

With reference to FIGS. 3-6, second force/rotationtransmitting/converting assembly or articulation assembly 250 of adapterassembly 200 includes second drive shaft 252 rotatably supported withinouter housing 202. Second rotatable drive shaft 252 includes anon-circular or shaped proximal end 252 a configured for connection withsecond connector sleeve 222 which is connected to respective secondrotatable drive connector 106 b of surgical device 100 (FIG. 2). Secondrotatable drive shaft 252 further includes a gear 254 including aplurality of external teeth 254 a, such as a spur gear, keyed to, orintegrally formed on, a distal end 252 b thereof.

Articulation assembly 250 further includes a gear nut 256 rotatablycoupled to gear 254 of second rotatable drive shaft 252. Gear nut 256 isrotatably disposed within distal housing 202 b of outer housing 202 andis concentric with central longitudinal axis “X.” Gear nut 256 includesa cylindrical body 258 having external gear teeth 260 extending from anddisposed around an external surface 258 a of cylindrical body 258 andinternal threads 262 extending along an internal surface 258 b ofcylindrical body 258. External teeth 254 a of gear 254 of secondrotatable drive shaft 252 meshingly engages external gear teeth 260 ofgear nut 256 such that rotation of second rotatable drive shaft 252results in rotation of cylindrical body 258 of gear nut 256.

A screw 264 is disposed within cylindrical body 258, and includesexternal threads 264 a that are engaged with internal threads 262 ofcylindrical body 258. Screw 264 is slidably keyed to a stationary sleeve207 by hub 265 that, in turn, is keyed to center tube 205 so that screw264 is preventing from rotating as cylindrical body 258 of gear nut 256is rotated. In this manner, as gear nut 256 is rotated, screw 264 isaxially translated along internal surface 258 b of cylindrical body 258of gear nut 256 along central longitudinal axis “X.” An articulationbearing 266, such as a radial/thrust bearing, is disposed within aninternal surface 264 b of screw 264 and includes an inner race 266 athat is independently rotatable relative to an outer race 266 b.

Second drive converter assembly 250 of adapter assembly 200 furtherincludes an articulation bar 268 having a proximal portion 268 a securedto inner race 266 a of articulation bearing 266, such as by coupler 267,so that articulation bar 268 is both longitudinally translatable duringaxial movement of screw 264 and rotatable about center tube 205 duringrotation of adapter assembly 200 and surgical loading unit 300. A distalportion 268 b of articulation bar 268 includes a slot 268 c therein,which is configured to accept a flag of the articulation link 330 (FIG.7) of surgical loading unit 300. Articulation bar 268 functions as aforce transmitting member to components of surgical loading unit 300. Itis envisioned that articulation bearing 266 allows for free, unimpededrotational movement of surgical loading unit 300 when its anvil andcartridge assemblies 306 and 308 (FIG. 7) are in an approximatedposition and/or when anvil and cartridge assemblies 306 and 308 arearticulated.

In operation, as second proximal drive shaft 252 is rotated due to arotation of second connector sleeve 222, as a result of the rotation ofthe second rotatable drive connector 106 b of surgical device 100, gearnut 256 is caused to be rotated about center shaft 205. Rotation of gearnut 256, in turn, causes screw 264 to be axially translated alonginternal threads 262 of cylindrical body 258 of gear nut 256, which inturn causes articulation bar 268 to be axially translated relative toouter tube 204. As articulation bar 268 is translated axially,articulation bar 268, being coupled to articulation link 330 of surgicalloading unit 300, causes concomitant axial translation of articulationlink 330 of surgical loading unit 300 to effectuate an articulation oftool assembly 304 of surgical loading unit 300 (FIG. 7). Articulationbar 268, being secured to inner race 266 a of articulation bearing 266,is free to rotate about central longitudinal axis “X” relative to outerrace 266 b of articulation bearing 266.

As illustrated in FIGS. 3-5, third force/rotationtransmitting/converting assembly or rotation assembly 270 of adapterassembly 200 includes third rotatable drive shaft 272 rotatablysupported within outer housing 202. Third rotatable drive shaft 272includes a non-circular or shaped proximal end 272 a configured forconnection with third connector sleeve 224 which is connected torespective third rotatable drive connector 106 c of surgical device 100(FIG. 2). Third rotatable drive shaft 272 includes a spur gear 274 keyedto, or integrally formed, on a distal end 272 b thereof.

Rotation assembly 270 includes a two-piece rotation ring gear 276fixedly supported in and connected to distal housing 202 b of outerhousing 202 of adapter assembly 200. Rotation ring gear 276 defines aninternal array of gear teeth 276 a. Rotation ring gear 276 includes apair of diametrically opposed, radially extending protrusions 276 bprojecting from an outer edge thereof. Protrusions 276 b are disposedwithin recesses 201 defined in distal housing 202 b, such that rotationof rotation ring gear 276 results in rotation of distal housing 202 b,and vice a versa. A reversing spur gear 278 inter-engages spur gear 274of third rotatable drive shaft 272 to the internal array of gear teeth276 a of rotation ring gear 276.

In operation, as third rotatable drive shaft 272 is rotated, due to arotation of third connector sleeve 224, as a result of the rotation ofthe third rotatable drive connector 106 c of surgical device 100, spurgear 274 of third rotatable drive shaft 272 engages reversing spur gear278 causing reversing spur gear 278 to rotate. As reversing spur gear278 rotates, rotation ring gear 276 also rotates thereby causing outerhousing 202 to rotate. As outer housing 202 is rotated, outer tube 204is caused to be rotated about central longitudinal axis “X” of adapterassembly 200. As outer tube 204 is rotated, surgical loading unit 300,which is connected to distal cap 206 of adapter assembly 200, is alsocaused to be rotated about central longitudinal axis “X” of adapterassembly 200.

With reference to FIGS. 3 and 5, adapter assembly 200 includes anelectrical assembly 280 supported on and in outer housing 202.Electrical assembly 280 includes a plurality of electrical contactblades 282, supported on a circuit board 284, for electrical connectionto electrical pass-through connector 105 of surgical device 100 (FIG.2). Electrical assembly 280 serves to allow for calibration andcommunication of life-cycle information to the circuit board of surgicaldevice 100.

Electrical assembly 280 further includes a strain gauge 286 electricallyconnected to circuit board 284. First rotatable drive shaft 242 extendsthrough strain gauge 286, which provides a closed-loop feedback to afiring/clamping load exhibited by first rotatable drive shaft 242.

Electrical assembly 280 also includes a slip ring 288 non-rotatably andslidably disposed along drive coupling nut 244. Slip ring 288 is inelectrical connection with circuit board 284 and functions to permitrotation of first rotatable drive shaft 242 and axial translation ofdrive coupling nut 244 while still maintaining electrical contactthereof with at least another electrical component within adapterassembly 200, and while permitting the other electrical components torotate about first rotatable drive shaft 242 and drive coupling nut 244.

Turning now to FIGS. 1 and 7, an embodiment of a surgical loading unit300 is shown. Surgical loading unit 300 includes a proximal body portion302 and a tool assembly 304. Proximal body portion 302 is releasablyattached to distal cap 206 of adapter assembly 200, and tool assembly304 is pivotally attached to a distal end of proximal body portion 302.Tool assembly 304 includes an anvil assembly 306 and a cartridgeassembly 308. Cartridge assembly 308 is pivotal in relation to anvilassembly 306 and is movable between an open or unclamped position and aclosed or clamped position. Proximal body portion 302 includes at leasta drive assembly 320 and an articulation link 330.

Drive assembly 320 includes a flexible drive beam 322 having a distalend 322 a and a proximal engagement section 322 b. A proximal end ofproximal engagement section 322 b includes diametrically opposedinwardly extending fingers 322 c that engage a hollow drive member 324to fixedly secure drive member 324 to the proximal end of drive beam322. Drive member 324 receives connection member 248 of distal drivemember 246 of drive assembly 240 of adapter assembly 200 when surgicalloading unit 300 is attached to distal cap 206 of adapter assembly 200.

Cartridge assembly 308 of tool assembly 404 includes a staple cartridge310 removably supported in a carrier 312. Staple cartridge 310 defines acentral longitudinal slot 310 a, and a plurality of linear rows ofstaple retention slots 310 b positioned on each side of the centrallongitudinal slot 310 a. Each of the staple retention slots 310 breceives a single staple 314 and a portion of a staple pusher 316.During operation of surgical device 100, drive assembly 320 abuts anactuation sled 318 and pushes actuation sled 318 through the staplecartridge 310. As the actuation sled 318 moves through staple cartridge310, cam wedges of the actuation sled 318 sequentially engage staplepushers 316 to move staple pushers 316 vertically within stapleretention slots 310 b and sequentially eject a single staple 314therefrom for formation against an anvil plate 306 a of anvil assembly306.

Proximal body portion 302 of surgical loading unit 300 includes anarticulation link 330 having a hooked proximal end 330 a which extendsfrom a proximal end of surgical loading unit 300 which is received inslot 268 c of distal portion 268 b of articulation bar 268 ofarticulation assembly 250 when surgical loading unit 300 is attached todistal cap 206 of adapter assembly 200. Articulation link 330 has adistal end 330 b pivotably secured to tool assembly 304.

Persons skilled in the art will understand that the structures andmethods specifically described herein and shown in the accompanyingfigures are non-limiting exemplary embodiments, and that thedescription, disclosure, and figures should be construed merely asexemplary of particular embodiments. It is to be understood, therefore,that the present disclosure is not limited to the precise embodimentsdescribed, and that various other changes and modifications may beeffected by one skilled in the art without departing from the scope orspirit of the disclosure. Additionally, the elements and features shownor described in connection with certain embodiments may be combined withthe elements and features of certain other embodiments without departingfrom the scope of the present disclosure, and that such modificationsand variations are also included within the scope of the presentdisclosure. Accordingly, the subject matter of the present disclosure isnot limited by what has been particularly shown and described.

What is claimed is:
 1. An adapter assembly for selectivelyinterconnecting a surgical loading unit and a surgical device, theadapter assembly comprising: an adapter housing configured to connect toa surgical device; an outer tube having a proximal end supported by theadapter housing and a distal end configured to connect to a surgicalloading unit; and a transmission assembly at least partially disposedwithin the adapter housing, the transmission assembly including: aproximal rotation receiving member connectable to a drive shaft of asurgical device; a distal force transmitting member connectable to anaxially translatable drive member of a surgical loading unit; at leastone pin securely disposed within the adapter housing; and a bearingassembly coupled to the proximal rotation receiving member and thedistal force transmitting member, the bearing assembly being axiallymovable along the at least one pin in response to rotational motion ofthe proximal rotation receiving member thereby axially moving the distalforce transmitting member.
 2. The adapter assembly according to claim 1,wherein the bearing assembly is non-rotatably disposed within theadapter housing.
 3. The adapter assembly according to claim 1, whereinthe bearing assembly includes a bearing housing and a bearing rotatablydisposed within the bearing housing.
 4. The adapter assembly accordingto claim 3, wherein the distal force transmitting member is coupled toan inner race of the bearing.
 5. The adapter assembly according to claim3, wherein the bearing housing further includes a threaded borethreadably coupled to a threaded distal end of the proximal rotationreceiving member.
 6. The adapter assembly according to claim 5, whereinthe threaded bore includes an insert molded threaded member.
 7. Theadapter assembly according to claim 6, wherein the insert molded treadedmember is formed from a polymer selected from the group consisting offluoropolymers, polystyrenes, and polyaryletherketones.
 8. The adapterassembly according to claim 1, wherein the at least one pin is coupledto a support ring member disposed within the adapter housing.
 9. Anelectromechanical surgical system, comprising: a surgical loading unitincluding a proximal body portion, a tool portion, and an axiallytranslatable drive member; a surgical device including a device housingand at least one rotatable drive shaft supported in the device housing;and an adapter assembly configured to selectively interconnect thesurgical loading and the surgical device, the adapter assemblyincluding: an adapter housing configured to connect to the surgicaldevice; an outer tube having a proximal end supported by the adapterhousing and a distal end configured to connect to the surgical loadingunit; and a transmission assembly at least partially disposed within theadapter housing, the transmission assembly including: a proximalrotation receiving member connectable to the rotatable drive shaft ofthe surgical device; a distal force transmitting member connectable tothe axially translatable drive member of the loading unit; at least onepin securely disposed within the adapter housing; and a bearing assemblycoupled to the proximal rotation receiving member and the distal forcetransmitting member, the bearing assembly being axially movable alongthe at least one pin in response to rotational motion of the proximalrotation receiving member thereby axially moving the distal forcetransmitting member.
 10. The electromechanical surgical system accordingto claim 9, wherein the axially translatable drive member is configuredto articulate the tool portion.
 11. The electromechanical surgicalsystem according to claim 9, wherein the bearing assembly isnon-rotatably disposed within the adapter housing.
 12. Theelectromechanical surgical system according to claim 9, wherein thebearing assembly includes a bearing housing and a bearing rotatablydisposed within the bearing housing.
 13. The electromechanical surgicalsystem according to claim 12, wherein the distal force transmittingmember is coupled to an inner race of the bearing.
 14. Theelectromechanical surgical system according to claim 12, wherein thebearing housing further includes a threaded bore threadably coupled to athreaded distal end of the proximal rotation receiving member.
 15. Theelectromechanical surgical system according to claim 14, wherein thethreaded bore includes an insert molded threaded member.
 16. Theelectromechanical surgical system according to claim 15, wherein theinsert molded treaded member is formed from a polymer selected from thegroup consisting of fluoropolymers, polystyrenes, andpolyaryletherketones.
 17. The electromechanical surgical systemaccording to claim 9, wherein the at least one pin is coupled to asupport ring member disposed within the adapter housing.